Extend C# control flow elements with type mentions

csharp/ql/lib/semmle/code/csharp/ExprOrStmtParent.qll

@@ -121,6 +121,13 @@ private module Cached {
     result = getAChildExpr(parent)
     or
     result = parent.getAChildStmt()
+    or
+    result =
+      any(TypeMention tm |
+        tm.getTarget() = parent
+        or
+        tm.getParent+().getTarget() = parent
+      )
   }
 
   private predicate parent(ControlFlowElement child, ExprOrStmtParent parent) {

csharp/ql/lib/semmle/code/csharp/Type.qll

@@ -6,6 +6,7 @@ import Generics
 import Location
 import Namespace
 import Property
+import semmle.code.csharp.controlflow.ControlFlowElement
 private import Conversion
 private import semmle.code.csharp.metrics.Coupling
 private import TypeRef
@@ -1286,7 +1287,7 @@ class TupleType extends ValueType, @tuple_type {
  * A type mention, that is, any mention of a type in a source code file.
  * For example, `int` is mentioned in `int M() { return 1; }`.
  */
-class TypeMention extends @type_mention {
+class TypeMention extends ControlFlowElement, @type_mention {
   Type type;
   @type_mention_parent parent;
 
@@ -1319,13 +1320,13 @@ class TypeMention extends @type_mention {
    * }
    * ```
    */
-  TypeMention getParent() { result = parent }
+  override TypeMention getParent() { result = parent }
 
   /** Gets a textual representation of this type mention. */
-  string toString() { result = type.toString() }
+  override string toString() { result = type.toString() }
 
   /** Gets the location of this type mention. */
-  Location getLocation() { type_mention_location(this, result) }
+  override Location getALocation() { type_mention_location(this, result) }
 }
 
 /**

csharp/ql/lib/semmle/code/csharp/controlflow/ControlFlowElement.qll

@@ -20,7 +20,7 @@ class ControlFlowElementOrCallable extends ExprOrStmtParent, TControlFlowElement
  */
 class ControlFlowElement extends ControlFlowElementOrCallable, @control_flow_element {
   /** Gets the enclosing callable of this element, if any. */
-  Callable getEnclosingCallable() { none() }
+  Callable getEnclosingCallable() { enclosingCallable(this, result) }
 
   /** Gets the assembly that this element was compiled into. */
   Assembly getAssembly() {

csharp/ql/lib/semmlecode.csharp.dbscheme

@@ -219,7 +219,7 @@ overlayChangedFiles(
 /** ELEMENTS **/
 
 @element = @declaration | @stmt | @expr | @modifier | @attribute | @namespace_declaration
-         | @using_directive | @type_parameter_constraints | @externalDataElement
+         | @using_directive | @type_parameter_constraints | @type_mention | @externalDataElement
          | @xmllocatable | @asp_element | @namespace | @preprocessor_directive;
 
 @declaration = @callable | @generic | @assignable | @namespace;
@@ -1369,7 +1369,7 @@ compiler_generated(unique int id: @element ref);
 
 /** CONTROL/DATA FLOW **/
 
-@control_flow_element = @stmt | @expr | @parameter;
+@control_flow_element = @stmt | @expr | @parameter | @type_mention;
 
 /* XML Files */
 

python/ql/lib/semmle/python/dataflow/new/internal/ImportResolution.qll

@@ -9,19 +9,7 @@ private import semmle.python.dataflow.new.DataFlow
 private import semmle.python.dataflow.new.internal.ImportStar
 private import semmle.python.dataflow.new.TypeTracking
 private import semmle.python.dataflow.new.internal.DataFlowPrivate
-
-/**
- * Holds if `init` is a package's `__init__.py` and `var` is a global variable in
- * `init` whose name matches a submodule of the package.
- *
- * Inlined from `SsaSource::init_module_submodule_defn` to avoid pulling
- * `semmle.python.essa.SsaDefinitions` into the new dataflow stack.
- */
-private predicate initModuleSubmoduleDefn(GlobalVariable var, Module init) {
-  init.isPackageInit() and
-  exists(init.getPackage().getSubModule(var.getId())) and
-  var.getScope() = init
-}
+private import semmle.python.essa.SsaDefinitions
 
 /**
  * Python modules and the way imports are resolved are... complicated. Here's a crash course in how
@@ -338,7 +326,7 @@ module ImportResolution {
     // imported yet.
     exists(string submodule, Module package, EssaVariable var |
       submodule = var.getName() and
-      initModuleSubmoduleDefn(var.getSourceVariable(), package) and
+      SsaSource::init_module_submodule_defn(var.getSourceVariable(), package.getEntryNode()) and
       m = getModuleFromName(package.getPackageName() + "." + submodule) and
       result.asCfgNode() = var.getDefinition().(EssaNodeDefinition).getDefiningNode()
     )

shared/controlflow/codeql/controlflow/ControlFlowGraph.qll

@@ -224,13 +224,6 @@ signature module AstSig<LocationSig Location> {
    */
   default AstNode getTryElse(TryStmt try) { none() }
 
-  /**
-   * Gets the `else` block of loop statement `loop`, if any.
-   *
-   * Only some languages (e.g. Python) support `for-else` constructs.
-   */
-  default AstNode getLoopElse(LoopStmt loop) { none() }
-
   /** A catch clause in a try statement. */
   class CatchClause extends AstNode {
     /** Gets the variable declared by this catch clause. */
@@ -1585,17 +1578,10 @@ module Make0<LocationSig Location, AstSig<Location> Ast> {
           n2.isBefore(loopstmt.getBody())
           or
           n1.isAfterValue(cond, any(BooleanSuccessor b | b.getValue() = while.booleanNot())) and
-          (
-            n2.isBefore(getLoopElse(loopstmt))
-            or
-            not exists(getLoopElse(loopstmt)) and n2.isAfter(loopstmt)
-          )
+          n2.isAfter(loopstmt)
           or
           n1.isAfter(loopstmt.getBody()) and
           n2.isAdditional(loopstmt, loopHeaderTag())
-          or
-          n1.isAfter(getLoopElse(loopstmt)) and
-          n2.isAfter(loopstmt)
         )
         or
         exists(ForeachStmt foreachstmt |
@@ -1604,11 +1590,7 @@ module Make0<LocationSig Location, AstSig<Location> Ast> {
           or
           n1.isAfterValue(foreachstmt.getCollection(),
             any(EmptinessSuccessor t | t.getValue() = true)) and
-          (
-            n2.isBefore(getLoopElse(foreachstmt))
-            or
-            not exists(getLoopElse(foreachstmt)) and n2.isAfter(foreachstmt)
-          )
+          n2.isAfter(foreachstmt)
           or
           n1.isAfterValue(foreachstmt.getCollection(),
             any(EmptinessSuccessor t | t.getValue() = false)) and
@@ -1621,11 +1603,7 @@ module Make0<LocationSig Location, AstSig<Location> Ast> {
           n2.isAdditional(foreachstmt, loopHeaderTag())
           or
           n1.isAdditional(foreachstmt, loopHeaderTag()) and
-          (
-            n2.isBefore(getLoopElse(foreachstmt))
-            or
-            not exists(getLoopElse(foreachstmt)) and n2.isAfter(foreachstmt)
-          )
+          n2.isAfter(foreachstmt)
           or
           n1.isAdditional(foreachstmt, loopHeaderTag()) and
           n2.isBefore(foreachstmt.getVariable())